Preparation method of lithium nickel manganese cobalt positive electrode material, lithium ion battery positive electrode material and lithium ion battery

Abstract

The invention belongs to the technical field of a lithium ion battery, and relates to a preparation method of a lithium nickel manganese cobalt positive electrode material, a lithium ion battery positive electrode material and a lithium ion battery. The preparation method of the lithium nickel manganese cobalt positive electrode material, provided by the invention, comprises the following steps of preparing a ternary material precursor aqueous solution with weight concentration being 45-60%; preparing a lithium source compound aqueous solution with weight concentration being 20-30%; sending the ternary material precursor aqueous solution and the lithium source compound aqueous solution to an agitator by a pump, and performing uniform mixing and stirring to obtain a suspension liquid; performing spray drying on the suspension liquid to obtain lithium mixed powder; and sintering the lithium mixed power to obtain the lithium nickel manganese cobalt positive electrode material. By the preparation method, the mixing efficiency of a precursor and a lithium source compound and the mixed grain uniformity can be improved; and meanwhile, the preparation method is convenient to operate and easy to control and is moderate in reaction condition, and the prepared positive electrode material has excellent electrochemical performance.

Description

technical field [0001] The invention belongs to the technical field of lithium ion batteries, and in particular relates to a preparation method of a nickel-cobalt lithium manganese oxide positive electrode material, a lithium ion battery positive electrode material and a lithium ion battery. Background technique [0002] In the existing secondary battery system, lithium-ion batteries are currently the most competitive secondary batteries in terms of development space and technical indicators such as life, specific energy, working voltage and self-discharge rate. The key material of lithium-ion batteries is the cathode material, which accounts for about 30% of the cost of lithium-ion batteries. At present, the positive electrode materials used in lithium-ion batteries on the market mainly include lithium cobalt oxide, lithium iron phosphate, lithium manganese oxide, and nickel-cobalt lithium manganate ternary materials. Nickel cobalt lithium manganate ternary material is a n...

AI Technical Summary

Problems solved by technology

In the existing preparation method, the step of mixing the lithium source and the precursor must be experienced, and then the existing precursor mixed lithium technology still has the problem of uneven mixing, resulting in poor uniformity of the mixed lithium precursor, which in turn leads to Lithium-rich or lithium-deficient samples appear after sintering, and the stability between batches is poor, which affects various performance indicators of the material, and the electrochemical performance of the product cannot be guaranteed

In the existing ternary material preparation methods, there are still defects such as nickel, cobalt, and manganese, which cannot be fully and uniformly mixed, cannot fully exert their respective functions, and the bulk density of the synthesized powder material is low.

In addition, the existing preparation method steps are complex, the process steps are too long, too many compounds are added, the reaction process is difficult to control, and the cost is high, which is not conducive to practical application

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